Immunological impact of cytokines on the chikungunya virus pathophysiology: A literature narrative review.

The chikungunya virus (CHIKV) is a member of the genus Alphavirus, family Togaviridae. CHIKV causes an acute systemic febrile condition, accompanied by severe polyarthralgia, intense muscle pain, and maculopapular exanthema, which may still occur in many patients. In rare cases, unusual symptoms may occur, eventually worsening the condition and resulting in a fatal outcome. It is a single-stranded, non-segmented RNA virus with a genome of approximately 11,805 nucleotides that organises a genetic and molecular chain that encodes non-structural proteins (nsP1, nsP2, nsP3, nsP4) and structural proteins (E3, E2, 6K, and E1). The fundamental role of immune response in the evolution of the disease is known. Understanding the role of immune response in the pathogenesis of CHIKV infection is challenging. In this context, innate and adaptive immune responses establish a connective interface that induces the production of various mediators that modulate the strategy of inhibiting viral replication. However, the immune escape articulated by the virus indicates that the action of pro-and anti-inflammatory cytokines contributes to the worsening of the disease and potentiates tissue damage with joint involvement. In this review, we discuss the role of the primary pro-and anti-inflammatory cytokines in the immunopathological processes of chikungunya fever.

Chemotaxonomic Differentiation of Pinus Species Based on n-Alkane and Long-Chain Alcohol Profiles of Needle Cuticular Waxes.

n-Alkane and long-chain alcohol (LCOH) profiles of needle cuticular waxes of nine provenances of three Pinus species (P. taeda. P. pinaster and P. pinea) were determined and their chemotaxonomic importance was studied. n-Alkanes concentrations were very low in all Pinus spp. A lack of ability of these compounds to differentiate Pinus spp. and their provenances was observed. LCOH concentrations were much higher, being nonacosan-10-ol (10-C29 -OH) the most abundant one in all Pinus spp. Total LCOH concentrations varied (P<0.001) between Pinus spp. with P. taeda presenting the highest (P<0.05) value and P. pinea the lowest one. Differences in LCOH profiles were large (P<0.001) and allowed separation of Pinus spp. in the Principal Component Analysis (PCA). Although a noticeable separation of individuals was not observed. cluster analysis on LCOH concentrations allowed a clear distinction between species, indicating their potential to be used as chemotaxonomic markers to differentiate provenances of different Pinus spp.

Acute quetiapine overdose is associated with risk of ectopic atrial rhythm.

Quetiapine overdose is commonly associated with coma, respiratory depression, hypotension, tachycardia, and QTc interval prolongation on the electrocardiogram.

3D Printable Dynamic Hydrogel: As Simple as it Gets!

3D printing technology offers a vast range of applications for tissue engineering applications. Over the past decade a vast range of new equipment has been developed; while, 3D printable biomaterials, especially hydrogels, are investigated to fit the printability requirements. The current candidates for bioprinting often require post-printing cross-linking to maintain their shape. On the other hand, dynamic hydrogels are considered as the most promising candidate for this application with their extrudability and self-healing properties. However, it proves to be very difficult to match the required rheological in a simple material. Here, this study presents for the first time the simplest formulation of a dynamic hydrogel based on thiol-functionalized hyaluronic acid formulated with gold ions that fulfill all the requirements to be printed without the use of external stimuli, as judged by the rheological studies. The printability is also demonstrated with a 3D printer allowing for the printing of the dynamic hydrogel as it is, achieving 3D construct with a relatively good precision and up to 24 layers, corresponding to 10 mm high. This material is the simplest 3D printable hydrogel and its mixture with cells and biological compounds is expected to open a new era in 3D bioprinting.

In vivo evaluation of anti-Leishmania activity of alkyltriazoles and alkylphosphocholines by oral route.

The failures in the treatment of leishmaniasis is an increasing problem around the world, especially related to resistance. Thus, we describe the synthesis and in vivo anti-Leishmania activity of alkylphosphocholine and alkyltriazoles; besides, their likely action mechanisms stem from some eventual inhibition of parasite enzymes using computational tools. These compounds were tested in an in vivo hamster model infected with Leishmania Leishmania infantum chagasi. Fifty days after parasite inoculation, the two compounds 12-azidedodecylphosphocholine (3) and 3-(1-(12-fluorododecyl)-1H-1,2,3-triazol-1-yl)propano-1-ol (9), were separately administered once a day as oral suspensions (25 and 12.5 mg/kg/day, respectively) during ten days, and their efficacy was compared to the reference compound pentavalent antimonial Glucantime (GLU). Compound 3 significantly reduced the number of parasites in the spleen (4.93 × 102 amastigotes/g) and liver (4.52 × 103 amastigotes/g). Compound 9 reduced the number of amastigotes in the spleen to 1.30 × 104 and 1.36 × 103 amastigotes/g in the liver. GLU was the most effective overall treatment (7.50 × 101 and 2.28 × 102 amastigotes/g in the spleen and liver, respectively). The high activity levels of these compounds in vivo may stem from their high in vitro leishmanicidal activity and lipophilicity. The in silico absorption, distribution, metabolism, and excretion studies also showed some anti-Leishmania potential. Compound 9 had more lipophilic characteristics than those of compound 3. In silico studies of the nine enzymes of compounds 3 and 9 showed significant evidence of interactions with nicotimidase and tyrosine aminotransferase, demonstrating possible inhibition enzymes present in L. (L.) infantum chagasi. These compounds could be a promising template for developing a new class of leishmanicidal agents, by oral route, and deserve further investigation to explore different therapeutic regimens.

Effect of green tea extract on gelatin-based films incorporated with lemon essential oil.

The use of natural polymers, such as gelatin and other proteins, has increased in an attempt to replace part of the consumption of petroleum-based packaging. This study evaluated the influence of green tea extract and lemon nanoemulsion on mechanical, thermal and permeability properties of gelatin matrix. The results showed that green tea increased the gelatin tensile strength (TS) from 86 ± 7 MPa to 101 ± 5 MPa, on the other hand, the nanoemulsion decreases to 78 ± 8 MPa. The incorporation of green tea and nanoemulsion enhanced the water vapor permeability of gelatin film; this could be due to the interacting with the hydrophobic domains of gelatin. This was indicated by melting point (Tm) in differential scanning calorimetry (DSC) and degradation temperatures in the thermogravimetric analysis (TG), respectively. Changes in FTIR spectra of gelatin film were observed when the green tea and nanoemulsion were incorporated. Therefore, this study showed a new characterization and formulation of gelatin films incorporated by green tea extract and lemon nanoemulsion and their potential for edible film.

Investigation of 8-methoxy-3-(4-nitrobenzoyl)-6-propyl-2H-chromen-2-one as a promising coumarin compound for the development of a new and orally effective antileishmanial agent.

Changes in host immunity and parasite resistance to drugs are among the factors that contribute to decreased efficacy of antiparasitic drugs such as the antimonial compounds pentamidine, amphotericin (AMP B) and miltefosine. Bioactive natural products could be alternatives for the development of new drugs to treat neglected human diseases such as leishmaniasis. Natural coumarins and synthetic analogues have shown leishmanicidal activity, mainly in vitro. This study investigated the in vitro and in vivo leishmanicidal activity of synthetic coumarin compounds (C1-C5) in parasites Leishmania (L.) amazonensis and L. (L.) infantum chagasi. The cytotoxicity of these compounds in mammalian cells and their influence on production of reactive oxygen species was also investigated. In vitro assays showed that 8-methoxy-3-(4-nitrobenzoyl)-6-propyl-2H-chromen-2-one (C4) was as active as AMP B mainly in the amastigote form (p < 0.05); C4 presented a selectivity index (65.43) four times higher than C2 (15.4) in L. amazonensis and six times higher (33.94) than C1 (5.46) in L. infantum chagasi. Additionally, coumarin C4 reduced the H2O2 concentration 32.5% more than the control group in L. amazonensis promastigotes during the lag phase of proliferation. No interference of C4 was observed on the mitochondrial membrane potential of the parasites. In vivo, coumarin C4 in corn oil (oral route) led to a reduction in the number of amastigotes from L. infantum chagasi to 1.31 × 106 and 4.09 × 104 in the spleen and liver, respectively (p < 0.05). Thus, C4 represents a candidate for further studies aiming at new treatments of leishmaniasis.

Synthesis and evaluation of the antileishmanial activity of silver compounds containing imidazolidine-2-thione.

A new series of silver compounds could be of interest on designing new drugs for the treatment of leishmaniasis. The compounds [Ag(phen)(imzt)]NO3(1), [Ag(phen)(imzt)]CF3SO3(2), [Ag(phen)2](BF4)·H2O (3), [Ag2(imzt)6](NO3)2(4), and imzt have been synthesized and evaluated in vitro for antileishmanial activity against Leishmania. (L.) amazonensis (La) and L. (L.) chagasi (Lc), and two of them were selected for in vivo studies. In addition to investigating the action on Leishmania, their effects on the hydrogen peroxide production and cysteine protease inhibition have also been investigated. As for antileishmanial activity, compound (4) was the most potent against promastigote and amastigote forms of La (IC50 = 4.67 and 1.88 µM, respectively) and Lc (IC50 = 9.35 and 8.05 µM, respectively); and comparable to that of amphotericin B, reference drug. Beside showing excellent activity, it also showed a low toxicity. In the in vivo context, compound (4) reduced the number of amastigotes in the liver and spleen when compared to the untreated group. In evaluating the effect of the compounds on Leishmania, the level of hydrogen peroxide production was maintained between the lag and log phases; however, in the treatment with compound (4) it was possible to observe a reduction of 25.44 and 49.13%, respectively, in the hydrogen peroxide rates when compared to the lag and log phases. It was noticed that the presence of a nitrate ion and imzt in compound (4) was important for the modulation of the antileishmanial activity. Thus, this compound can represent a potentially new drug for the treatment of leishmaniasis.

Comparative analysis of real-time PCR assays in the detection of canine visceral leishmaniasis.

Dogs are important hosts and reservoirs of leishmaniasis, a disease caused by protozoan parasites from the genus Leishmania, affecting ~12 million people worldwide. The detection of visceral leishmaniasis (VL) in dogs by real-time PCR (qPCR) may improve on diagnosis, but the different qPCR methods available for Leishmania DNA detection have not been established as routine in diagnostic tools and/or epidemiologic studies for canine VL. Here, we compared three qPCR assays (DNApol, Linj31, and LDON) in the detection of VL by Leishmania infantum in spleen (n = 48; 7), skin (n = 48; 7), and whole blood (n = 44; 7) samples from serologically positive and negative dogs, respectively. Overall, the DNApol performed better than the Linj31 and LDON assays in the detection of positive samples in all tissues tested, yielding from 66.7 to 100.0% of positivity for both skin and spleen samples. For spleen samples, we observed no statistically significant differences between positive detection by the LDON and DNApol assays. Whole blood samples yielded the lowest rates of positive detection, regardless of the qPCR assay used. In contrast, positive detection of Leishmania DNA was as efficient from skin samples using the DNApol assay as from spleen samples using either the DNApol or the LDON assay. Although qPCR assays from skin samples may not be practical for use in the field, our study suggests that the DNApol and LDON assays from skin samples could be used in future to evaluate canine VL treatment in veterinary clinics.

Bread formulated with guava powder was enriched in phenolic and aroma compounds, and was highly acceptable by consumers.

Guava powder (GP) was used as source of aroma and phenolic compounds to fortify wheat bread 10% (GB10) and 20% (GB20), substituting for wheat flour. Phenolic compounds, antioxidant capacity, volatile compounds profile, and sensory acceptability of control bread (CB; without GP) and guava breads (GB) were evaluated. Incorporation of GP increased roughly 2-to-3-fold the phenolic compounds contents of bread. Ten phenolic compounds were identified in GB20, and quercetin-3-O-rutinoside was the major compound, while in CB, ferulic acid was the major among the six phenolic compounds in CB. Bread making seemed to promote the release of phenolic compounds from structural components. Breads incorporated with GP presented a richer volatile profile than CB, especially due to the presence of terpenes. GB improved aroma profile of bread. GP added aroma compounds and phenolic antioxidants, and seemed to be an interesting approach to enhance bread bioactivity and acceptability.

The transcription factor MEF/ELF4 regulates the quiescence of primitive hematopoietic cells.

The transcriptional circuitry that regulates the quiescence of hematopoietic stem cells is largely unknown. We report that the transcription factor known as MEF (or ELF4), which is targeted by the t(X;21)(q26;q22) in acute myelogenous leukemia, regulates the proliferation of primitive hematopoietic progenitor cells at steady state, controlling their quiescence. Mef null HSCs display increased residence in G0 with reduced 5-bromodeoxyuridine incorporation in vivo and impaired cytokine-driven proliferation in vitro. Due to their increased HSC quiescence, Mef null mice are relatively resistant to the myelosuppressive effects of chemotherapy and radiation. Thus, MEF plays an important role in the decision of stem/primitive progenitor cells to divide or remain quiescent by regulating their entry to the cell cycle.

The antihypersensitive and antiinflammatory activities of a benzofuranone derivative in different experimental models in mice: the importance of the protein kinase C pathway.

BACKGROUND: Benzofuranone (BF1) was synthesized and its effects evaluated on mechanical hypersensitivity and paw edema models induced by different agents and on neuropathic pain induced by partial ligation of the sciatic nerve. An attempt was also made to elucidate the mechanism of action. METHODS: Swiss mice were used for the tests. Hypersensitivity was induced by intraplantar injection of carrageenan, bradykinin (BK), prostaglandin E2 (PGE2), epinephrine, lipopolysaccharide, or complete Freund adjuvant or by using a neuropathic pain model (evaluated with von Frey filament 0.6 g). The antiinflammatory effects were investigated in a paw edema model induced by carrageenan, PGE2, and BK (measured with a plethysmometer). The involvement of protein kinase C (PKC) was investigated through a nociception model induced by phorbol myristate acetate. RESULTS: BF1 inhibited the hypersensitivity and paw edema induced by intraplantar injection of carrageenan, BK, and PGE2 (P < 0.001), and it was effective in reducing the hypersensitivity evoked by complete Freund adjuvant or epinephrine (P < 0.001) but not by lipopolysaccharide (P = 0.2570). BF1 inhibited the licking behavior induced by phorbol myristate acetate (P < 0.001), suggesting involvement of the PKC pathway. A reduction in hypersensitivity of mice submitted to partial ligation of the sciatic nerve (P < 0.001) was observed, with inhibition of neutrophil migration and interleukin-1ß production into the spinal cord. BF1 treatment did not interfere with locomotor activity (P = 0.0783) and thermal withdrawal threshold (P = 0.5953), which are important adverse effects of other analgesics. CONCLUSIONS: BF1 has dose-dependent antihypersensitive and antiinflammatory effects in both acute and chronic models of pain and inflammation, possibly mediated through interference with the PKC activation pathway. The easy and fast synthesis of this compound, low-cost, low-concentration-requirement, and once-daily-administration drug suggest it as a candidate for future clinical studies.

Cell-Free Nuclear and Mitochondrial DNA as Potential Biomarkers for Assessing Sepsis Severity.

Sepsis continues to be a significant public health challenge despite advances in understanding its pathophysiology and management strategies. Therefore, this study evaluated the value of cell-free nuclear DNA (cf-nDNA) and cell-free mitochondrial DNA (cf-mtDNA) for assessing the severity and prognosis of sepsis. Ninety-four patients were divided into three groups: infection (n = 32), sepsis (n = 30), and septic shock (n = 32). Plasma samples were collected at the time of diagnosis, and cfDNA concentrations were determined by qPCR assay. The results showed that plasma cfDNA levels increased with the severity of the disease. To distinguish between patients with infection and those with sepsis, the biomarker L1PA290 achieved the highest AUC of 0.817 (95% CI: 0.725-0.909), demonstrating a sensitivity of 77.0% and a specificity of 79.3%. When cf-nDNA was combined with the SOFA score, there was a significant improvement in the AUC (0.916 (0.853-0.979)), sensitivity (88.1%), and specificity (80.0%). Moreover, patients admitted to the ICU after being diagnosed with sepsis had significantly higher cf-nDNA concentrations. In patients admitted to the ICU, combining cf-nDNA with the SOFA score yielded an AUC of 0.753 (0.622-0.857), with a sensitivity of 95.2% and a specificity of 50.0%. cfDNA can differentiate between patients with infection and those with sepsis. It can also identify patients who are likely to be admitted to the ICU by predicting those with indications for intensive care, suggesting its potential as a biomarker for sepsis.

Severe COVID-19 and long COVID are associated with high expression of STING, cGAS and IFN-α.

The cGAS-STING pathway appears to contribute to dysregulated inflammation during coronavirus disease 2019 (COVID-19); however, inflammatory factors related to long COVID are still being investigated. In the present study, we evaluated the association of cGAS and STING gene expression levels and plasma IFN-α, TNF-α and IL-6 levels with COVID-19 severity in acute infection and long COVID, based on analysis of blood samples from 148 individuals, 87 with acute COVID-19 and 61 in the post-COVID-19 period. Quantification of gene expression was performed by real-time PCR, and cytokine levels were quantified by ELISA and flow cytometry. In acute COVID-19, cGAS, STING, IFN-α, TNF-α, and IL-6 levels were higher in patients with severe disease than in those with nonsevere manifestations (p < 0.05). Long COVID was associated with elevated cGAS, STING and IFN-α levels (p < 0.05). Activation of the cGAS-STING pathway may contribute to an intense systemic inflammatory state in severe COVID-19 and, after infection resolution, induce an autoinflammatory disease in some tissues, resulting in long COVID.

Synthesis of high solids content low surfactant/polymer ratio nanolatexes.

A new two-stage strategy for the synthesis of high-solids-content low-surfactant/polymer ratio nanolatexes was developed. In the first stage, the knowledge-based strategy is used to obtain 18 wt % nanolatexes with the maximum number of particles and using a fraction of the surfactant. In the second stage, the rest of the surfactant is employed to stabilize these particles while they are growing to reach the target solids content. The final particle size results from the interplay between limited particle coagulation and secondary homogeneous nucleation during the second stage. Smaller particle sizes were obtained for surfactants able to desorb from the existing particles and diffuse quickly to the newly formed particles. Waterborne nanoparticles as small as 32 nm in diameter were obtained with 36 wt % solids content and solids content/(surfactant/polymer) ratio higher than 26. This represents a substantial improvement with respect to the best results reported in the literature (dp = 32 nm; 23 wt % solids, and solids content/(surfactant/polymer) = 21).

Antitumor and anti-cachectic effects of shark liver oil and fish oil: comparison between independent or associative chronic supplementation in Walker 256 tumor-bearing rats.

BACKGROUND: Shark liver oil (SLOil) and fish oil (FOil), which are respectively rich in alkylglycerols (AKGs) and n-3 polyunsaturated fatty acids (PUFAs), are able to reduce the growth of some tumors and the burden of cachexia. It is known that FOil is able to reduce proliferation rate and increase apoptotic cells and lipid peroxidation of tumor cells efficiently. However, there are few reports revealing the influence of SLOil on these parameters. In the current study, effects of FOil chronic supplementation on tumor growth and cachexia were taken as reference to compare the results obtained with SLOil supplementation. Also, we evaluated if the association of SLOil and FOil was able to promote additive effects. METHODS: Weanling male Wistar rats were divided into 4 groups: fed regular chow (C), supplemented (1 g/kg body weight) with SLOil (CSLO), FOil (CFO) and both (CSLO + FO). After 8 weeks half of each group was inoculated with Walker 256 cells originating new groups (W, WSLO, WFO and WSLO + FO). Biochemical parameters of cachexia, tumor weight, hydroperoxide content, proliferation rate and percentage of apoptotic tumor cells were analysed. Fatty acids and AKG composition of tumor and oils were obtained by high performance liquid chromatography and gas chromatography - mass spectrometry, respectively. Statistical analysis was performed by unpaired t-test and one-way ANOVA followed by a post hoc Tukey test. RESULTS: Fourteen days after inoculation, SLOil was able to restore cachexia parameters to control levels, similarly to FOil. WSLO rats presented significantly lower tumor weight (40%), greater tumor cell apoptosis (~3-fold), decreased tumor cell proliferation (35%), and higher tumor content of lipid hydroperoxides (40%) than observed in W rats, but FOil showed more potent effects. Supplementation with SLOil + FOil did not promote additive effects. Additionally, chromatographic results suggested a potential incorporation competition between the n-3 fatty acids and the AKGs in the tumor cells' membranes. CONCLUSIONS: SLOil is another marine source of lipids with similar FOil anti-cachectic capacity. Furthermore, despite being less potent than FOil, SLOil presented significant in vivo antitumor effects. These results suggest that the chronic supplementation with SLOil may be adjuvant of the anti-cancer therapy.

Effect of intake of iron-fortified milk on levels of ferritin and hemoglobin in preschoolers: A systematic review and meta-analysis.

BACKGROUND: Food fortification is often the simplest way to increase iron intake on a broad and sustainable basis. It is one of the most cost-effective global development efforts. OBJECTIVE: To systematize data from randomized and nonrandomized controlled trials investigating the effect of consumption of iron-fortified milk (IFM) on serum iron status in preschoolers. METHODS: The trials were systematically searched in five electronic databases that evaluated the effect of iron-fortified milk (IFM) consumption on hemoglobin and ferritin in children aged 1-6 years. The randomized the meta-analysis model was used to calculate total and stratified effects. RESULTS: Seven trials representing 1210 preschoolers showed a significant effect of IFM on hemoglobin [difference in means (MD) 0.33 g/dL (95% CI 0.23, 0.44; I2 = 3.85%, p (Q statistic) < 0.01)] and ferritin concentrations [effect size (SMD) 0.57 (95% CI 0.19, 0.95; I2 = 84.63%, p (Q statistic) < 0.01)]. In stratified analyses, hemoglobin showed an increase when subjects received iron with other co-interventions [MD 0.35 g/dL (95% CI 0.22, 0.48; I2 = 11.01%; p (Q statistic) = 0.36)]; and when the iron dose was above 5 mg/day [MD 0.34 g/dL (95% CI 0.23, 0.45; I2 = 2.33%; p (Q statistic) = 0.37)] and the intervention time was over 6 months [MD 0.39 g/dL (95% CI 0.18, 0.60; I2 = 37.90%; p (Q statistic) = 0.20)]. For ferritin, stratified analyses showed a larger effect size when they used dose higher than 5 mg/day [SMD 0.60 (95% CI 0.02, 1.18; I2 = 91.06, p (Q statistic) < 0.01)] and intervention was conducted longer than 6 months [SMD 0.96 (95% CI - 0.16, 1.76; I2 = 93.38%, p (Q statistic) < 0.01)]. CONCLUSIONS: Our findings indicate that although milk iron fortification modestly increases serum hemoglobin levels or the effect size of serum ferritin of participants, it cannot be considered in the coadjuvant treatment for anemia. Register: CRD42020213604.

Cross-cultural adaptation and validation of Sarcopenia and Quality of Life (SarQoL) in Brazil.

BACKGROUND: Sarcopenia is defined as a slow, progressive, and apparently inevitable process of involuntary loss of muscle mass, strength, and quality, which occurs with advancing age. It is widely accepted that sarcopenia can directly affect quality of life. OBJECTIVE: Translate, adapt and validate the "Sarcopenia and Quality of Life" instrument (SarQoL) to the Brazilian context. DESIGN AND SETTINGS: Translation, cross-cultural adaptation, and validation study carried out at the Federal University of São Carlos, São Carlos, São Paulo, Brazil. METHODS: The population consisted of 221 older adult participants. The steps recommended by the guidelines from the authors of the original instrument were followed sequentially: initial translation, synthesis of translations, backward translation, evaluation by a panel of judges, pre-test, and analysis of psychometric properties. The translation and adaptation process was conducted as recommended. RESULTS: Two hundred and twenty-one participants took part in the step analysis of the psychometric properties of SarQoL, in which 55 presented sarcopenia. Cronbach's alpha coefficient of the total SarQoL questionnaire was 0.976, indicating excellent internal consistency. Excellent agreements between the test and retest with an Interclass Correlation Coefficient (ICC) of 0.983 (95% confidence interval: 0.901-0.996) were observed in the SarQoL domains. The domains of Short-Form 36 and EuroQoL 5-dimension showed significant correlation, from moderate to strong magnitude, with SarQoL total score, indicating convergent validity. CONCLUSION: The Brazilian version of SarQoL presented evidence of reliability and validity.

Leishmania (L.) infantum chagasi isolated from skin lesions of patients affected by non-ulcerated cutaneous leishmaniasis lead to visceral lesion in hamsters.

In Central America, Leishmania (L.) infantum chagasi infection causes visceral leishmaniasis (VL) and non-ulcerated cutaneous leishmaniasis (NUCL). The aim of the present study was to evaluate the course of an experimental infection in hamsters caused by L. (L.) infantum chagasi isolated from patients affected by NUCL compared with a strain isolated from a patient with VL. Stationary phase parasites in culture were inoculated through subcutaneous and intraperitoneal routes in hamsters. Following the post-infection times, a histopathological study, parasite load and cytokine determination in skin from the cutaneous inoculation site and viscera were performed. Animals subcutaneously infected with the different strains did not develop macroscopic lesions at the inoculation site, and the histopathological changes in the dermis were very slight. Regarding the histopathological study of the viscera, we observed the portal mononuclear inflammatory infiltrate, the presence of nodules in the hepatic parenchyma and the proliferation of macrophages in the spleen, which increased over the infection course. Overall, the parasite load in the liver and spleen and in the total IgG titres in the sera of infected hamster showed an increase with the time of infection, regardless of the route of inoculation. Regarding cellular immunity, we did not observe an increase or decrease in pro- and anti-inflammatory cytokines compared to the healthy control, except for IL-10, which was evident in the infected animals. The data showed that strains isolated from NUCL cause visceral lesions in the hamsters regardless of the route of inoculation, and they were similar to parasites isolated from VL humans.

Bacteria and antimicrobial resistance profile during the composting process of wastes from animal production.

Livestock waste is widely used in agriculture. Although they provide benefits to the soil, and consequently to plants, they have the potential to contaminate the environment, as they contain pathogenic microorganisms and determinants of antimicrobial resistance, if not properly managed. Therefore, this study aims to evaluate the effect of composting horse bedding and poultry litter in organic and conventional production systems on the occurrence of bacteria in the Enterobacteriales order and to identify their antimicrobial resistance profiles. Bacterial strains were isolated from Salmonella-Shigella and eosin methylene blue solid media from animal waste during the composting process that was conducted for 125 days. After isolation, the strains were identified by the MALDI-TOF technique; the disk diffusion test was then performed for phenotypic detection of antimicrobial resistance. A total of 158 bacterial strains were isolated during composting of three wastes. The Enterobacteriaceae family was the most abundant, whereas Proteus mirabilis and Escherichia coli were the species with the highest percentage in the wastes, which also exhibited a multi-resistance profile. Poultry litter showed a greater abundance of resistant bacteria than horse bedding did. Similarly, a greater number of resistant bacteria was detected in conventional poultry litter than in organic poultry litter. The results obtained reinforce that animal wastes are reservoirs of pathogenic bacteria that are resistant to antimicrobials and highlight the importance of developing management strategies that aim to reduce and/or eliminate these contaminants to guarantee their safe use in agriculture.